From: Ville Syrjälä <ville.syrj...@linux.intel.com> intelFastRenderClippedPoly() renders the polygon using triangles. For polygons the provoking vertex is always the first one, and currently this function assumes that the provoking vertex for triangles is the last one. In case the user changed the provoking vertex convention, the hardware may be configured to treat the first vertex of triangles as the provoking vertex. So check the convention and emit the triangles in the appropriate order to avoid having to change the hardware provoking vertex convention for rendering polygons.
Signed-off-by: Ville Syrjälä <ville.syrj...@linux.intel.com> --- src/mesa/drivers/dri/i915/intel_tris.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/src/mesa/drivers/dri/i915/intel_tris.c b/src/mesa/drivers/dri/i915/intel_tris.c index 2c0a785..2b62104 100644 --- a/src/mesa/drivers/dri/i915/intel_tris.c +++ b/src/mesa/drivers/dri/i915/intel_tris.c @@ -928,10 +928,18 @@ intelFastRenderClippedPoly(struct gl_context * ctx, const GLuint * elts, GLuint const GLuint *start = (const GLuint *) V(elts[0]); int i, j; - for (i = 2; i < n; i++) { - COPY_DWORDS(j, vb, vertsize, V(elts[i - 1])); - COPY_DWORDS(j, vb, vertsize, V(elts[i])); - COPY_DWORDS(j, vb, vertsize, start); + if (ctx->Light.ProvokingVertex == GL_LAST_VERTEX_CONVENTION) { + for (i = 2; i < n; i++) { + COPY_DWORDS(j, vb, vertsize, V(elts[i - 1])); + COPY_DWORDS(j, vb, vertsize, V(elts[i])); + COPY_DWORDS(j, vb, vertsize, start); + } + } else { + for (i = 2; i < n; i++) { + COPY_DWORDS(j, vb, vertsize, start); + COPY_DWORDS(j, vb, vertsize, V(elts[i - 1])); + COPY_DWORDS(j, vb, vertsize, V(elts[i])); + } } } -- 2.0.5 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev